Defect and Diffusion Forum最新文献

{"title":"Correlation of Extended Defects with Electrical Yield of SiC MOSFET Devices","authors":"D. Baierhofer, B. Thomas, F. Staiger, B. Marchetti, C. Förster, T. Erlbacher","doi":"10.4028/p-i82158","DOIUrl":"https://doi.org/10.4028/p-i82158","url":null,"abstract":"The quality of the silicon carbide (SiC) epitaxial layer, i.e., layer homogeneities and extended defect densities, is of highest importance for high power 4H-SiC trench metal-oxide-semiconductor field effect transistors (Trench-MOSFET) devices. Especially, yield for devices with a large chip area is severely impacted by extended defects. Previously, devices had to be fully manufactured to effectively gauge the impact of a reduction in extended defect densities in the epitaxial layers on device yield. The production of devices such as Trench-MOSFETs is an extensive procedure. Therefore, a correlation between extended defects in the epitaxial layer and electrical device failure would allow to reliably estimate the impact of process changes during epitaxial layer deposition on electrical device yield.For this reason, n-type epitaxial layers were grown on around 1,000 commercially available 150 mm 4H-SiC Si-face substrates, which received a chemical wet cleaning prior to the epitaxy deposition. Substrates with lowest micro-pipe density from two different suppliers were used. The wafers were characterized with the corresponding device layout for defects utilizing surface microscopy as well as ultraviolet photoluminescence techniques. Subsequently, these wafers were used to produce more than 500,000 Trench-MOSFET devices. All devices have been tested on wafer level for their initial electrical integrity.With these methods a precise correlation between extended defects in the epitaxial layer and electrical failures on wafer level could be found. The influence of different substrates on the defect-based yield prediction regarding the electrical yield on wafer level is discussed. Additionally, a calculated kill-ratio is presented and the severity of defect classes on initial device failure, e.g., stacking faults, and their key failures modes are discussed.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"11 - 16"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48939187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Strain in Ion Implanted 4H-SiC by Fringes Observed in Synchrotron X-Ray Topography","authors":"Zeyu Chen, Ya Fei Liu, Hongyu Peng, Q. Cheng, S. Hu, B. Raghothamachar, M. Dudley, R. Ghandi, S. Kennerly, P. Thieberger","doi":"10.4028/p-di3si0","DOIUrl":"https://doi.org/10.4028/p-di3si0","url":null,"abstract":"A novel high energy implantation system has been successfully developed to fabricate 4H-SiC superjunction devices for medium and high voltages via implantation of dopant atoms with multi-energy ranging from 13 to 66 MeV to depths up to 12um. Since the level of energies used is significantly higher than those employed for conventional implantation, lattice damage caused by such implantation must be characterized in detail to enhance the understanding of the nature of the damage. In regard to this, by employing the novel high energy system, 4H-SiC wafers with 12μm thick epilayers were blanket implanted by Al atoms at energies ranging from 13.8MeV to 65.7MeV and N atoms at energies ranging up to 42.99MeV. The lattice damages induced by the implantation were primarily characterized by Synchrotron X-ray Plane Wave Topography (SXPWT). 0008 topographs recorded from the samples are characterized by an intensity profile consisting of multiple asymmetric diffraction peaks with an angular separation of only 2” (arcseconds). Using Rocking-curve Analysis by Dynamical Simulation (RADS) program, diffracted intensity profile was used to extract the corresponding strain profile indicating an inhomogeneous strain distribution across the depth of the implanted layer.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"51 - 56"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49466535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implementation of Large Scale Deep Learning Non-Destructive Methods for Characterizing 4H-SiC Materials","authors":"R. Leonard, Matthew Conrad, E. van Brunt, J. Witry, E. Balkas","doi":"10.4028/p-08c7e9","DOIUrl":"https://doi.org/10.4028/p-08c7e9","url":null,"abstract":"A whole wafer method for industrial high volume, non-destructive characterizing of extended defects is demonstrated for 150 mm and 200 mm 4H-SiC wafers. Deep learning (DL) coupled with non-destructive techniques (NDT, DL-NDT) involving high volume, fast optical microscopy methods correlates industry accepted chemistry and physics-based etch and diffraction techniques for defect characterization. The application of the DL-NDT method is shown to reproduce defect distributions achieved by accepted etch techniques for extended defects of threading dislocations (TD), basal plane dislocations (BPD), and threading screw dislocations (TSD). An example of algorithm development is described to show progress toward implementing the method, as well as DL-NDT defect density compared to etch density for multiple wafers. The development status for implementing this technique for large-scale industrial wafer production includes etch validation of the results to ensure the technique is consistent and reliable. The ability to use this non-destructive technique ultimately will result in better correlation with device behavior and provide feedback to crystal growth processes to improve substrate wafers, while reducing the need for etch methods.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"3 - 9"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48720547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Basal Plane Dislocation Motion Induced by p+ Ion Implantation Using Synchrotron X-Ray Topography","authors":"Zeyu Chen, Ya Fei Liu, Hongyu Peng, Q. Cheng, S. Hu, B. Raghothamachar, M. Dudley, Stephen A. Mancini, S. Jang, Woongje Sung","doi":"10.4028/p-4mo61y","DOIUrl":"https://doi.org/10.4028/p-4mo61y","url":null,"abstract":"Multiple PIN diodes with junction termination extension (JTE) were fabricated on 4H-SiC wafers with 10 μm thick epilayers by ion implantation with various dosages of Al ions at room temperature (RT) and high temperature (600 °C). The subsequent annealing process was conducted at 1650 °C for 10 minutes to activate the dopant atoms and recover the lattice damages introduced by the implantation. Synchrotron X-ray topography was used to characterize the defects in the devices, and it is observed that basal plane dislocations (BPDs) were generated during the annealing process from the boundaries between the high (P+) and low (P-) doping concentration in devices implanted with relatively high doses at RT. Further, topographs also manifest motion of BPDs due to implantation-induced stresses, where BPDs with opposite sign Burgers vectors move in directions accommodative of nature of stress (tensile/compressive). On the other hand, generation of BPDs due to implantation was not observed in devices implanted either at relatively low dosages at both temperatures or relatively high dosages at high temperature. Measurements of blocking behaviors of devices illustrate that devices with higher densities of process-induced BPDs yield higher leakage currents.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"71 - 78"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45049732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stacking Faults Originating from Star-Defects in 4H-SiC","authors":"Sami A. El Hageali, N. Mahadik, R. Stahlbush, H. Guthrey, S. Johnston, Jake Soto, B. Odekirk, B. Gorman, M. Al‐Jassim","doi":"10.4028/p-0yob2s","DOIUrl":"https://doi.org/10.4028/p-0yob2s","url":null,"abstract":"Intense efforts are currently in progress to study various sources of basal plane dislocations (BPDs) in SiC epitaxial layers. BPDs can generate Shockley-type stacking faults (SSFs) in SiC epitaxial layers, which have been shown to be associated with the degradation of power devices. This study shows that the star-shaped defect can be a source of several BPDs in the epitaxial layer. We investigate the complex microstructure of the star defect, the generation of BPDs, and expansion of SSFs using various complementary microscopy and optical techniques. We show direct evidence that star-defects can be a nucleation point of single-SSFs that can expand at the core of the defect. Newly found secondary dislocation arrays extending over a few centimeters away are found to be emanating from the primary arms of the star defect. The presence of such dislocation walls and the expansion of single-SSFs will affect the yield of numerous die on a wafer. Further understanding of the formation mechanism of stacking faults generated from star-defects as provided in this study helps understand their effect on SiC-based devices, which is crucial to assess device reliability.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"29 - 33"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41371242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Study on Coldflame Propagation Characteristics Applying Amplified Ignition Source to Overcome Landfill gas’s Flame Retardant Limit","authors":"K. Ryu, Munseok Choe","doi":"10.4028/p-55to7c","DOIUrl":"https://doi.org/10.4028/p-55to7c","url":null,"abstract":"In this study combustion characteristics were analyzed with LFG, one of the alternative energy sources of SI engines. To overcome the flame retardant limit, which is the shortcoming of LFG, the combustion characteristics were analyzed using the AIS device that was created for this study’s purpose. A static combustion chamber to which AIS can be applied was designed for the experiment that was conducted on the coldflame propagation and combustion characteristics of each LFG fuel using C-type (conventional ignition type) and AIS devices. From the basic LFG experiment, it was identified that as the proportion of carbon dioxide in the fuel increased, the combustibility decreased, and the combustion pressure decreased. When using the AIS device to overcome the flame retardancy of LFG, the combustion pressure was increased by 2 bar even in LFG70 and LFG60, where combustion was actively occurring with the C-type and the combustibility was improved in LFG50 as well. In overall respects, it was judged that the use of AIS could overcome the flame retardancy of LFG and could incorporate LFG into SI engines.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"81 - 92"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46858059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of Aircraft Fuel Dump Rate towards the Mitigation of Post-Impact Fire","authors":"Abdulbaqi Jinadu, O. Olayemi, J. Daniel, Oluwatomiwa John Odenibi, V. Koloskov, D. Tiniakov","doi":"10.4028/p-gz5an7","DOIUrl":"https://doi.org/10.4028/p-gz5an7","url":null,"abstract":"This study seeks to improve the utilization of compressed air towards a faster fuel jettisoning, to increase the survival rate of passengers in the event of an accident or aborted takeoffs by augmenting the already existing means of dumping fuel with no considerable increase in overall weight. The aircraft fuel dump sub-system was isolated, this process was achieved with the aid of the venturi effect. The engine compressor marks the start of the aircraft fuel dump sub-system while an exterior nozzle for displacing the fuel marks its end. This system achieved jettisoning through bled-off air from the compressor, passing through a converging-diverging nozzle (primary supersonic nozzle), thereby creating a vacuum in the mixing chamber. A jet which provides a direct connection between the fuel tank and the mixing chamber sucks fuel from the tank, where bypassed air from the compressor expels the sucked air in fine particles. After running the simulation, the mass flow rate was computed. The compressed air inlet has a mass flow rate of 58.5193(Kg/S), the kerosene inlet 1.2385(Kg/S) while the outlet has a relative value of-59.6541(Kg/S).This study seeks to improve the utilization of compressed air towards a faster fuel jettisoning, to increase the survival rate of passengers in the event of an accident or aborted takeoffs by augmenting the already existing means of dumping fuel with no considerable increase in overall weight. The aircraft fuel dump sub-system was isolated, this process was achieved with the aid of the venturi effect. The engine compressor marks the start of the aircraft fuel dump sub-system while an exterior nozzle for displacing the fuel marks its end. This system achieved jettisoning through bled-off air from the compressor, passing through a converging-diverging nozzle (primary supersonic nozzle), thereby creating a vacuum in the mixing chamber. A jet that provides a direct connection between the fuel tank and the mixing chamber sucks fuel from the tank, where bypassed air from the compressor expels the sucked air in fine particles. After running the simulation, the mass flow rate was computed. The compressed air inlet has a mass flow rate of 58.5193(Kg/s), and the kerosene inlet 1.2385(kg/s) while the outlet has a relative value of -59.6541(kg/s).","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"127 - 140"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46932929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Strain in 3C-SiC/Si Epiwafers from X-Ray Diffraction Measurements","authors":"M. Zielinski, Mark E. Bussel, H. Mank, S. Monnoye, M. Portail, A. Michon, Y. Cordier, V. Scuderi, F. La Via","doi":"10.4028/p-jf4ooe","DOIUrl":"https://doi.org/10.4028/p-jf4ooe","url":null,"abstract":"X-Ray diffraction measurements of lattice parameter were performed for (111) and (100) oriented 3C-SiC/Si epiwafers. Strain of 3C-SiC epilayer and Si substrate were estimated and the result was compared with routine wafer deformation measurements. An unexpected discrepancy was observed between XRD and curvature measurements for (100) oriented samples.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"65 - 69"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48344627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrodynamic Stability Analysis for MHD Casson Fluid Flow through a Restricted Channel","authors":"S. Adesanya, T. A. Yusuf, Adesina Taofeek Adeosun, L. Rundora","doi":"10.4028/p-np7v6f","DOIUrl":"https://doi.org/10.4028/p-np7v6f","url":null,"abstract":"Flow instability is a major challenge experienced in medical, engineering and industrial settings globally. For instance, flow instability linked with irregular cardiac output of the heart leads to organ malfunctioning in the medical field, it also encourages mechanical vibrations in the case of fluctuating flow rate, and several other applications. In this study, linear stability analysis is conducted to monitor the behavior of a small disturbance that is imposed on hydromagnetic Casson fluid that flows steadily through a saturated porous medium. A new variant of the Orr-Sommerfield equation is obtained and solved numerically by using spectral point collocation weighted residual approach with eigenfunction expansion of the Chebyshev polynomial as the admissible trial function. Based on the QZ algorithm, numerical results are obtained for wave and Reynold’s numbers, wave velocity as functions of Magnetic field intensity and porosity shape parameters. Results are validated against previously released data. The biophysics of the heart, particularly in cardiac rhythm analysis, as well as several other medicinal and technical applications, is among the areas where the current work has applicability.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"115 - 126"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47950724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Minority Carrier Traps Induced by Neutron Reactions with 4H-SiC","authors":"M. Belanche, M. E. Bathen, Piyush Kumar, C. Dorfer, C. Martinella, U. Grossner","doi":"10.4028/p-724d7y","DOIUrl":"https://doi.org/10.4028/p-724d7y","url":null,"abstract":"This work presents the characterization of minority carrier traps in epitaxial n-type 4H-SiC after high fluence neutron irradiation using minority carrier transient spectroscopy (MCTS) in a temperature range of 20 K to 660 K. Three minority carrier trap levels are reported, labelled as X, B and Y, whose activation energies were estimated by Arrhenius analysis and where the B level is assigned to substitutional boron (BSi). The dynamic behaviour of the trap levels was studied by consecutive temperature scans.","PeriodicalId":11306,"journal":{"name":"Defect and Diffusion Forum","volume":"426 1","pages":"23 - 28"},"PeriodicalIF":0.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48246851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}